Hydraulic jack



May 13, 1930- f c. M. BANKS 1,758,640

HYDRAULI C JACK Filed Nov. 5, 1928 2 Sheets-Sheet l Z .Vl

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HYDRAULI C JACK Filed Nov. 3, 1928 2 Sheets-Sheet .2

Fatented May 13, 193@ 'r Fries I-IYDRAULC JACK Application filedNovember 3, 1928. Serial No. 317,050.

This invention relates to hydraulic jacks and the main object oi theinvention is to provide a jack which is simple and durable inconstruction and eiiicient in operation.

-Another object is to provide a jack which may be rapidly operated andwhich has an eft- .ficient release valve positive and convenient inoperation.

rlhe foregoing and other objects together with means whereby the samemay be carried into effect will best be understood from the 'followingdescription ot a preferred embodiment of the invention taken inconnection with the accompanying drawing in which- Figure 1 is avertical, central section through the jack, certain of the elementsbeing shown in elevation.

Figure 2 is a plan view thereof.

Figure 3 is a detail of the release valve removed from its seat.

Figure l is a detail view of a modiiication oil the upper end or" theplunger or ram showing an auxiliary extensible and retractile workengaging member.

Figure 5 is a detail of a handle for use in operating the jack.

In carrying out the invention I provide a relatively elongated base 1having the upwardly directed jack cylinder 2 at one end and the recess 3at its opposite end spaced from the cylinder 2 and connected therewithby an angularly disposed port or passage 4. A threaded filler plug 5seated in an upwardly countersunk portion 8 of the base serves as ameans for filling the device with oil as well as draining the oil fromthe same when necessary. A cylindrical ram or plunger 7 is slidablymounted in the jack cylinder 2, the same having the piston rings 8 atits lower end and the circular, relatively enlarged work engaging head 9at its upper end. A collar 10 threadedly engages the upper end of thejack .cylinder 2 and has the inwardlj-,fY directed annular lip 11adapted to overlie and retain in place the wipe washer 12 which excludesdust and other foreign matter from the cylinder. A. guide and stop rod13 threadedly engages the head 9 and 14 and depends along the side cithe ack cylinder 2 in parallelism therewith, the said rod being slidablypassed through a bracket 15 secured to the cylinder and provided at itsend with a stop 16 in such manner that it will limit the upward movement(to be described) oi' the plunger and prevent the same from rotating inthe said jack cylinder.

The recess 3 is provided with an upstanding, exteriorly threaded annulus17 upon which is threadedly mounted the pump cylinder 18 ot' relativelysmaller diameter and length than the jack cylinder 2 as shown. An inletvalve denoted generally at 19 is positioned in the lower end ot the pumpcylinder 18 abutting against the upper edge of the annulus 17. 'lhe saidinlet valve 19 comprises an outer body portion 20 having a central seat21 the upper portion 22 of which is flared upwardly and the lowerportion 23 iared downwardly as shown in Figure 1. A valve 24 having acomplementary tapered face is adapted toseat upwardly in this lowerportion 23 and the same has a flange 25 adapted to engage the bodyportion 2O to limit the seating action of the valve as will beunderstood. The valve 24 is normally held seated by means of anexpansion coil spring 26 mounted upon a pin 27 directed upwardly from asemi-circular bracket 28 aiiixed at its ends to the lower surface of thebody 20 and extended downwardly therefrom, the upper end of the saidspring 2G entering into a recess 29 in the lower surface of the valve.

A piston 30 is mounted in the pump cylinder 18 and the same is providedwith a piston rod 3l extending upwardly through a conventional gland 32seated in the cap 33 which is threadedly mounted over the upper end ofthe said cylinder 18. A pivot lug 34 is secured to the wall of the jackcylinder 2 above the level of the pump cylinder 18 and an operatinglever 35 having the biurcated end 36 is pivotally attached by a pin 37to the lug, the said operating lever 35 being angularly bent in the tormof a V as shown. A link 38 is pivotally connected at its ends by pins 39to the upper end of the piston rod 31 and tl e lower point of theoperating lever 35. The outer end of the said operating lever 35 issquared as at t() to receive the socket end 41 of an operating handle 42by means of lUU which the piston 30 may be reciprocated within thecylinder for a purpose to be described.

A release valve casing 43 is extended angularly from the base 1 beneaththe annulus 17, the axis of this casing being parallel with the extendedaxis of the port or passage 4. The cylindrical casing 43 is providedwith a threaded mouth 44 and terminates at its inner end in a taperedvalve seat 45, a small port or passage 46 communicating thru this seatwith the recess o in the base 1. An elongated cylindrical valve 47 isinserted in the casing 43 the expanded outer end having threads at 48 toengage the threaded mouth of the casing and a tapered inner end 49 toengage the seat 45. The said valve 47 also has a longitudinal groove 50beginning at the tapered end 49 and passing along the valve asubstantial distance then turning circumfere'ntially and passingpartially around the valve as shown at 51. A small port or escapeaperture 52 is provided in the casing 43 in such manner that by properlypositioning the valve in the casing the groove 59 will register withthis aperture for a purpose to be described. The outwardly disposed endof the valve 47 is reduced and squared as at so that it will lit thesocket end 41 of the said operating handle 42, which handle is providedwith an arcuate hook 54 by means of which the acl; may be withdrawn fromunder any object.

In the use and operation of the device the j ack is inverted and anoperating fluid such as oil is poured into the jack through the fillerplug 5 until it reaches approximately the end of the ram or plunger 7,as the same stands telescoped within the cylinder 2. rEhen byreciprocating the piston 30 in the pump cylinder 18 in the manner setforth, air will be forced through the valve 19, recess 3 and passage 4forcing the ram or plunger upward as will be understood. The air cannotescape through the valve 19 since its pressure only serves to morelirmly close this valve. The air must be compressed in the pump cylinderuntil its pressure is sufficient to overcome the tension of the spring26 and the pressure of the air in the base 1 and cylinder 2, so that therise of the ram Vor plunger will be steady and even as will be undestood l/Vhen it is desired to release the. pressure in the jack andlower the plunger the release valve 47 is turned until the groove 50therein is brought into registry with the escape aperture 52 whereby theair may escape. t will be noted that since the groove in this valve 47is not only turned out yof registry with the aperture 52 but the taperedend 49 of the valve seats in the seat 45 when the jack is being raisedthe valve is tightly closed so that air cannot possibly escape, yet byturning the valve a part of a revolution the air may freely escape. ltwill also be noted that the jack may be placed in position, the plungercaused to rise, the pressure released and the jack then withdrawn bymeans of the single, simple handle 42. From the foregoing theefficiency, simplicity and ease of operation of the ack will beapparent.

ln Figure 4 is illustrated modilication of the construction of the workengaging head 9 upon the ram or plunger 7. In this ease an extensibleand retractile auxiliary member or head 55 with a threaded shank 56 isthreadedly mounted in the end of the said ram 7, the regular head 9thereof being provided with a recess 57 to receive this said head 55. Byunscrewing this auxiliary head 55 the jack may be closely adjusted tothe work so that the work may be raised to the full capacity of thejack. By screwing the head 55 downward the work may rest upon theregular large head 9.

TVhile l have herein set forth certain preferred embodiments of myinvention it is understood that l may vary from the same in minordetails so as best to construct a practical device for the purposesintended, not departing from the spirit of the invention and within thescope of the appended claim.

I claim:

in a hydraulic jack embodying a jack cylinder and plunger and anoperatively connected pump cylinder and compression piston, the assemblybeing vertically arranged and having a relief valve for the escape ofair, a compression valve in the pump cylinder below the compressionpiston, the same comprising an outer body portion having a entraiaperture and seat, the upper' portion of the seat being flared upwardlyand the lower portion being flared downwardly, a frusto-conical valvefor complementarily seating upwardly in the lower flared portion of thevalve seaty the same being centrally recessed in its lower face, andhaving a ange for engaging the under side of the body portion to limitthe seating action of the valve, a. sei'ni-circular bracket secured byits ends to the lower surface of the body portion at diametricallyopposite points, a pin extended from the bracket up into the said recessot the valve, and a coil spring` seated over the said pin and extendedunder compression up into the said recess of the valve and having abearing` against the valve for holding it to its seat.

In testimony whereof l my signature.

CHARLES M. BANKS.

